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Common causes of TV interference

at800 is committed to resolving and providing solutions to Freeview disruption caused by 4G at 800 MHz. However, there are many other things that can be the cause of Freeview disruption. Below is a list of some of the most common causes, and solutions to address them.

Internal/causes in the home

Induction or impulse interference

This kind of Freeview disruption comes from mains-powered household devices. It disrupts power to the Freeview device at the mains, causing a fluctuation in the electrical current. You can identify if one of one of your devices is causing your disruption by switching off the device.

COMMON CULPRITS ARE:

Washing machine

Tumble dryer

Central heating pump/combination boiler

Fridge

Freezer

Power tools

Vacuum cleaner

Water pump

Fluorescent light-starter

Solution: Fit a mains filter device to the mains connection to Freeview equipment. Keep aerial leads and connectors as far from electrical leads as possible.

In-house signal interference

COMMON CULPRITS ARE:

Mobile phones

Baby monitors

DECT phones

Walkie talkies

Solution: Avoid placing or using these devices near your TV and Freeview equipment.

External/causes from outside the home

Weather or atmospheric interference

COMMON CULPRITS ARE:

Heavy rain

Strong wind

Extended hot weather/high pressure atmospherics

Solution: In high winds or rain, the TV signal may be affected as your aerial or tall trees around it move in the wind. Wet leaves on can also weaken the signal. Upgrading your aerial or raising its height may help

High pressure, which brings fine weather, allows signals to reach areas they wouldn’t normally reach. Under normal circumstances, the signals from each television transmitter can only be received by those homes that have aerials with a direct line-of-sight to the transmitter. However on warm summer days, hot air can get trapped under colder air high up creating a layer which acts like a mirror for television signals, reflecting them back towards Earth. This can cause signals from different transmitters to overlap. Unfortunately, there is no solution to this kind of interference. Broadcasters can’t prevent it, and adjusting your aerial will make no difference. Reception will only improve when the weather changes.

Induction or impulse interference

This type of interference is caused by local machinery operations, from larger operations like roadworks to smaller operations such as mowing the lawn. These activities disrupt power to the Freeview device at the mains, causing fluctuation in the electrical current.

COMMON CULPRITS ARE:

Passing traffic

Road works e.g. pneumatic drills

Lawnmowers

Solutions: older cable that has degraded should be replaced as it can be susceptible to external interference.

External signal interference

COMMON CULPRITS ARE:

Taxi firms

Amateur radio setups

Police cars or stations

Solution: fitting a RF or UHF band pass filter should block this interference and stop it affecting your Freeview signal.

Physical barriers or impacts

This type of interference is caused by large objects getting in the way of the signal path, which results in signals being blocked on a permanent or temporary basis.

COMMON CULPRITS ARE:

New large buildings

Cranes

Trees

Solutions: issues caused by temporary structures will be resolved when the structure in removed. In more permanent cases, an amplifier could improve your reception of the signal.

Damage to external Freeview equipment

This type of interference/disruption is the result of damage to the external materials that allow you to receive Freeview signals.

EXAMPLES:

Storm damage to aerial – misalignment, damage

Old or damaged cables, down-leads or fly-leads

Solutions: Replace any damaged cables, down-leads or fly-leads. Also, make sure your aerial isn’t damaged, misaligned, or otherwise broken. For best results, you need a good quality rooftop aerial pointing directly at the appropriate digital transmitter.

Watch the how-to video

Support for property managers and landlords

We will write to homes, organisations, businesses and local authorities at least three weeks before the 4G services launch in the area.

For local authorities, we will write to your Chief Executive and Director of Housing. Regardless of whether your local authority has transferred its housing stock to a Housing Association, an ALMO or still manages it as council housing, we would expect that you will have other council properties receiving TV through an aerial, including council offices, libraries, resource or community centres. These could be affected by disruption.

Viewers living in communal properties with a shared aerial, who have received a postcard from us and notice new disruption to their Freeview service, are asked to contact us. We will also ask them to report the issue to you and ask them to provide us with your contact details.

If you are responsible for properties with communal aerials, and have been advised by your tenants of new disruption to Freeview services, you should contact us and register the details of the property or properties you manage.

We will provide a free communal filter – to you or your aerial contractor – which should be fitted to the communal aerial system and will enable viewers in all of the properties it serves to continue receiving and watching Freeview as normal.

In most cases, a simple filter installed between the aerial and the distribution amplifier in a communal TV system will restore Freeview. The communal filter will, in most cases, resolve the issue, however, we will provide domestic filters for the residents to fit themselves.

What if the filter doesn’t solve the issue?

If the communal and/or the domestic filter cannot fix the problem, and an acceptable level of TV reception is not restored, then call our contact centre. We can provide additional support and technical expertise. There is no charge for this service.

The contact centre will need details about the property and the nature of the problem. We can send an engineer to meet with your aerial contractor on site to check the filter has been fitted properly and is working correctly; provide advice on how to improve your TV reception and make recommendations about a different platform if needed.

We are not obliged to cover costs incurred by contractors for the fitting of communal filters. In certain cases, we may offer to assist with the installation of a communal filter. However, we will not undertake additional work to communal aerial systems beyond fitting the appropriate filter.

You are responsible for commercial or business properties

We will mail all properties in an area that might be affected by disruption at least three weeks before services launch in the area. If you use a satellite master antenna system (SMATV) service to provide TV services, you are not usually dependent on free to air signals via an aerial, and unlikely to be affected.

Many of these systems are maintained by an external contractor and they should be able to resolve any problems.

Support for local authorities

We write to households, businesses, hospitals, care homes*, schools, universities and MOD properties at least three weeks before 4G masts are switched on in the local area. If you are a local authority responsible for properties with a shared aerial, you may need to get a communal filter fitted to the aerial to enable viewers in all of the properties it serves to continue receiving and watching Freeview as normal.

The lease, tenancy agreement or title deeds (in Scotland) will provide details about the rights, role and responsibilities of the owner, tenant or property manager of a flat or apartment, and the provision of TV services within the block and to a property.

Communal filters

Some organisations may have specific TV provision, for example, internet protocol TV (IPTV) for delivering TV and broadband; outsourced patient bedhead TV and phone services. You may also have ancillary buildings and properties, such as staff facilities, classrooms, residential housing where TV is delivered through an individual or communal aerial. In either case, if new disruption is reported, we can help.

If you are responsible for properties with communal aerials, and you have been advised of new disruption to Freeview services, you should contact us and register the details of the property or properties you manage. You should also provide us with the contact details – including an email address – of your aerial contactor.

We will provide a free communal filter – to you or your aerial contractor – which should be fitted to the communal aerial system and will enable viewers in all of the properties it serves to continue receiving and watching Freeview as normal. If there is still a problem, filters will need to be fitted on the aerial cable behind the TV or set-top box. Your aerial contractor should be able to advise you and we are able to provide technical advice through our contact centre. The communal filter will, in most cases, resolve the issue, however, we will provide domestic filters for the residents to fit themselves.

Commercial or business properties

If you use a satellite master antenna system (SMATV) service to provide TV services and are not dependent on free to air signals via an aerial, it is unlikely you will be affected.

These systems may be maintained by an external contractor who should be able to resolve any problems.

Support for viewers with a shared aerial

If you are not responsible for your TV aerial (because this is the responsibility of your landlord or property manager or you live in a care home for example), have received a postcard from us and experience new disruption to your Freeview service, you should contact us.

We will also ask you to report the issue to your landlord, property manager, factor or residents’ association and ask you to provide us with their contact details. The lease, tenancy agreement or title deeds (in Scotland) will provide details about the rights, role and responsibilities of the owner, tenant or property manager of a flat or apartment, and the provision of TV services within the block and to a property.

What happens next?

We will assess whether the Freeview disruption might be due to 4G at 800 MHz; for example we will check whether a new mobile mast has recently been activated in your area.

We will aim to contact whoever you tell us is responsible for your communal aerial so we can arrange to provide the appropriate communal or domestic filters, free of charge. We can also provide household filters for residents if necessary.

If your landlord or property manager has a contracted aerial engineer, we can deliver the filters direct to them. For those without a contracted aerial engineer, or if the contracted engineer needs some help, at800 can provide technical advice/assistance. In certain cases, at800 may be able to assist with the installation of a communal filter; however, we are unable to undertake additional work to a communal aerial system beyond the fitting of the appropriate filter.

If the Freeview disruption is due to 4G at 800 MHz, then the communal filter fitted to the communal aerial system will enable viewers in all of the properties it serves to continue receiving and watching Freeview as normal.

TV manufacturers recommend the use of an outdoor aerial above roof height to provide good quality reception.

Types of set-top aerials

Despite this, more than two million TV sets in the UK rely on set-top aerials for signal reception. Generally this is down to costs rather than improved signal reliability.

Set-top aerials such as the ‘double loop’ variety are not particularly suited for viewing TV services in the UK. Not only are they quite poor at receiving UHF signals, they also tend not to filter out unwanted signals, interference and wrong frequencies.

Log periodic set-top aerials (those with a pointed shape) are a better design but still only offer relatively low reception quality.

All set-top aerials are a compromise on good aerial design.

1. MOVING THE SET-TOP AERIAL HIGHER CAN IMPROVE TV RECEPTION.

2. MOVING THE SET-TOP AERIAL CLOSER TO A WINDOW CAN HELP WITH TV RECEPTION, FOR WHICH YOU MAY NEED A LONGER LEAD.

3. TV RECEPTION COULD BE IMPROVED BY PLACING A LOW COST UPGRADE AERIAL OUTSIDE A WINDOW POINTING IN THE SAME DIRECTION AS A NEIGHBOUR’S AERIAL.

4. SET-TOP AERIALS WITH BOOSTERS BUILT IN ARE OFTEN TURNED UP TOO HIGH. REDUCING THE GAIN CONTROL TO A LOWER SETTING CAN HELP IMPROVE TV RECEPTION.

5. TV RECEPTION CAN BE IMPROVED BY MAKING SURE ALL CONNECTIONS ARE OF GOOD QUALITY AND REPLACING OLD OR BROKEN JOINTS AND CABLES

6.CALLING A LOCAL RDI/CAI AERIAL COMPANY AND ASKING FOR ADVICE ON LOCAL RECEPTION CONDITIONS COULD HELP

7. ASKING NEIGHBOURS WHAT’S THE BEST WAY TO GET TV RECEPTION LOCALLY COULD HELP IN OBTAINING A BETTER QUALITY TV RECEPTION. ACROSS THE UK, SHARED DISHES ARE AVAILABLE ON MANY COMMUNAL BUILDINGS. YOU COULD CONNECT TO ONE TO GET FREE-TO-AIR SATELLITE TV FROM FREESAT AND SKY.

8. CONSIDER FITTING AN AERIAL SYSTEM ON THE ROOF, AS THIS WILL PROVIDE BETTER QUALITY TV RECEPTION.

9. FREE LIVE INTERNET TV IS AVAILABLE FROM THE BBC, ITV, CHANNEL 4 AND MANY OTHER TV PROVIDERS. THIS IS A REAL ALTERNATIVE WHERE THERE ARE DIFFICULT-TO-RESOLVE TV RECEPTION ISSUES CAUSED BY SET TOP AERIALS. BUT DON’T FORGET YOU STILL NEED A TV LICENCE TO WATCH LIVE TV OVER THE INTERNET.

10. IF YOU HAVE TRIED ALL THESE THINGS, AND HAVE CONTACTED US AND BELIEVE NEW DISRUPTION TO YOUR RECEPTION COULD BE FROM 4G AT 800 MHZ SIGNALS, THEN TRY FITTING AN AT800 FILTER BETWEEN THE SET-TOP AERIAL AND TV SET OR DIGITAL BOX. THIS MAY HELP IMPROVE THE SIGNAL.

Support for viewers who may need a little extra help

We work with the voluntary and community sector to ensure those who may struggle with this issue receive support and advice from people they know and trust. This includes the provision of a chaperone to accompany a visit from an at800-accredited engineer, if required.

How do I know I can trust the chaperone?

Viewers can check if the chaperone is from at800 by calling our contact centre.

When the local support team calls to arrange the appointment, viewers can supply them with a password that only the viewer and they will know. When the engineer arrives at a viewer’s home, they will be asked for the password confirming it’s the designated team member.

Support for care homes

We will provide a communal filter and arrange for an engineer to visit care homes if we diagnose TV disruption is being caused by 4G at 800 MHz. Care home managers should call our contact centre for more information. Contact us for more information.

8 truths about the 4G network

You may have read a lot about 4G and how it might affect your Freeview TV service. Some of what you have heard may not be entirely accurate, here are 8 facts about the 4G roll-out.

Only new disruption to Freeview – which happens after 4G masts are switched on close to your home – could be due to 4G at 800 MHz. You are more likely to be affected if you live close to a new 4G mast, are in an area with weak digital TV reception or have a TV signal booster.

If you watch only Satellite or Cable TV, you won’t be affected by 4G at 800 MHz. If you experience disruption to your service, please contact your provider.

If you do experience disruption to Freeview – and have several terrestrial digital TVs which share an aerial – it’s likely that all will be affected.

Not all 4G masts might cause disruption to Freeview – only those working at 800 MHz.

In most cases, a simple easy-to-plug in filter will remedy the problem.

In some cases a filter may need be installed on your roof which will be done by an aerial engineer.

If you live in a block of flats or other high-rise building with a communal aerial, we will provide a communal filter and your landlord or management company will need to arrange to get it fitted.

at800 is here to help resolve any disruption to Freeview from 4G at 800 MHz. There is no charge to viewers for our service.

4G filters guide

For those households most at risk of experiencing disruption to Freeview from 4G at 800 MHz, we may send an at800-approved filter before new 4G mobile services go live. We recommend waiting to see if you experience problems with your Freeview service before fitting the at800 filter, as per the instructions.

If you require additional filters for multiple TV sets, we will provide these on request. However, if you have more than one Freeview TV in your house, you may have a single aerial and an ‘amplifier’ that sends the signal to different locations. If so, then one filter – fitted between the TV aerial and the amplifier – should resolve any disruption to Freeview on all of the TVs in your home. It is only if you have separate aerials for each of your TVs that you may need additional filters.

Different types of filters

We have at800-approved filters for different situations. A standard domestic filter is smaller than a pack of cards and does not need either batteries or a power supply.

The filters are small boxes that ‘block’ 4G signals at 800 MHz and enable you to carry on watching Freeview as normal. We have tested each type of at800-approved filter to ensure it works correctly in the UK.

If you only have a TV aerial and do not have an amplifier, the filter is fitted between your TV set and the aerial socket.

We think most viewers will be able to fit the domestic at800-approved filter themselves.

If you have an amplifier in your loft, for example, if you have a weak TV signal, the filter needs to be connected between the aerial and the amplifier.

If you have a rooftop aerial amplifier, a weatherproof filter needs to be attached to the mast and connected between the aerial and the masthead amplifier.

Do I need a channel 59 or 60 filter?

Freeview TV services are delivered on different frequencies (commonly known as UHF channels) from transmitters serving where you live in the UK.

One 8 MHz channel is able to carry a number of digital TV stations (for example BBC One, BBC Two, BBC Three etc) combined – or multiplexed – together to use the spectrum most efficiently. In order to receive and watch all channels available on Freeview, viewers need to receive six of these multiplexes. Transmitters across the UK use different sets of UHF frequency blocks to carry the multiplexes. For example, Crystal Palace in London transmits on channels 22, 23, 25, 26, 28 and 30.

If you receive one of your six digital TV multiplexes in UHF channel 60, and experience disruption to your Freeview service, then you will need a channel 60 filter. If you don’t receive any multiplexes in UHF channel 60 then a channel 59 filter should suffice.

To find out what UHF channel you use to receive Freeview, visit the Digital UK website and use the Coverage Checker. Select ‘Detailed view’ to see which TV transmitter you use.

CE marking

DTG Testing provide a conformance testing service for manufacturers wishing to supply at800 filters. The DTG testing service stipulates that filters must be CE compliant. Each product has its own set of compliance information which can be found here.

Filtronic – Filtronic – UK-PSD006-V3-P

Available from the following retailers

Ch59 filter, designed for home use, suitable for self-installation
* Suitable for most UK addresses, excluding Ch60 DTT coverage
* High performance ceramic technology, lower insertion loss in the TV band and high rejection of 4G
* Includes all accessories for installation including coax flying lead, attachment pad

Filtronic – Filtronic – UK-PSD008-V5-P

Available from the following retailers

Ch60 filter, designed for home use, suitable for self-installation
* Superior cut-off performance enables reception of all DTT channels including Ch60
* High performance ceramic technology, lower insertion loss in the TV band and high rejection of 4G
* Includes all accessories for installation including coax flying lead, attachment pad